/*

 * Licensed to the Apache Software Foundation (ASF) under one

 * or more contributor license agreements.  See the NOTICE file

 * distributed with this work for additional information

 * regarding copyright ownership.  The ASF licenses this file

 * to you under the Apache License, Version 2.0 (the

 * "License"); you may not use this file except in compliance

 * with the License.  You may obtain a copy of the License at

 *

 *     http://www.apache.org/licenses/LICENSE-2.0

 *

 * Unless required by applicable law or agreed to in writing, software

 * distributed under the License is distributed on an "AS IS" BASIS,

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

 * See the License for the specific language governing permissions and

 * limitations under the License.

 */

package com.bff.gaia.unified.runners.gaia.translation.functions;



import com.bff.gaia.unified.sdk.transforms.join.RawUnionValue;

import com.bff.gaia.unified.sdk.util.WindowedValue;

import com.bff.gaia.api.common.functions.FlatMapFunction;

import com.bff.gaia.util.Collector;



/** A Gaia function that demultiplexes output from a {@link GaiaExecutableStageFunction}. */

public class GaiaExecutableStagePruningFunction

    implements FlatMapFunction<RawUnionValue, WindowedValue<?>> {



  private final int unionTag;



  /**

   * Creates a {@link GaiaExecutableStagePruningFunction} that extracts elements of the given union

   * tag.

   */

  public GaiaExecutableStagePruningFunction(int unionTag) {

    this.unionTag = unionTag;

  }



  @Override

  public void flatMap(RawUnionValue rawUnionValue, Collector<WindowedValue<?>> collector) {

    if (rawUnionValue.getUnionTag() == unionTag) {

      collector.collect((WindowedValue<?>) rawUnionValue.getValue());

    }

  }

}